This invention relates to anchor pile connectors and in particular to releasable connectors for securing the tension legs of a tensioned leg platform. After an offshore well is drilled from a floating platform, it may be desirable to produce the well to a later-installed tensioned leg platform. These platforms, while supported by the buoyancy of the water, are not freely floating but are tied back to a plurality of anchors and tensioned from the seabed. Typically, a plurality of tension lines are located at each corner of the platform and all are maintained continuously in tension although the amount of tension may vary and the lines may vary up to 15 degrees from the vertical at the anchor location.
An anchor template is secured to the seabed with driven and/or drilled and cemented piles. The tension legs are run from the various anchor templates to the platform. Each is typically a 23 cm OD by 8 cm ID tubular member in threaded sections, operating under a nominal tension of 1,000 tons. For the purpose of inspecting these lines at a later date, it is desirable to retrieve the entire string of a particular leg while the remaining legs continue to carry the load.
In using a connector with a flexible joint therein all of the bending movement is taken by the flexible elements of the joint and the majority of the bending force is absorbed by the movement of the flexible portions. Tension placed on the connection occurs by a force passing through the pivot center of the joint with the force passed upwardly to the latch body by compression through the flexible bearing. This then passes the force through the upper portion of the fixed body of the flexible connector. When the connection between the fixed body and the template is in the lower portion of the body, the forces must pass through the body with resultant bending moments placed on the body and on the latch connection. By placing the latch connection above the center of pivoting of the flexible connector these forces may be passed directly into the template thereby reducing the forces placed on the fixed member of the flexible joint.
Still with this arrangement it is desirable to have a connector while will lock without the need for external operation and which will remained locked even though tension on the leg will be momentarily relaxed. It is also desirable that the connector be capable of being unlatched for retrieval of the leg as desired.